A wide variety of electronic devices are available for consumers today. Many of these devices have connectors that that facilitate communication with and/or charging of a corresponding device. These connectors often interface with other connectors through cables that are used to connect devices to one another. Sometimes, connectors are used without a cable to directly connect the device to another device, such as a charging station or a sound system.
As smart-phones, media players and other electronic devices become more compact, their corresponding connectors play a greater role in the ultimate market success of the device. For example, in many nano-scale MP3 players and compact flash storage devices, the connectors actually dominate the physical geometry, the aesthetics and sometimes the cost of the electronic device.
One of the most critical components of a connector are the contacts. The contacts are the portions of the connector that physically touch each other and are responsible for conducting the electrical signals between the mated connectors. Not only must these contacts survive sometimes thousands of mates and de-mates, they must also withstand the rigors of today's consumer, remaining with them throughout the day as they travel in and out of fitness centers, kitchens, offices, factories, automobiles, and many other places. Many of these locations provide opportunities for exposure to chemicals that pose little or no risk to the consumer, but present a harsh environment for the connector contacts. For example, connectors regularly come into contact with food, sweat, and other elements that corrode the materials that make up the connector contacts.
Connector contacts are often made primarily of copper alloys, due to the advantageous electrical properties of copper. However, copper alloys are highly susceptible to corrosion so the contacts are often covered with an outer layer of corrosion and oxidation resistant metal. One of the most common outer layers employed is gold because of its high electrical conductivity and resistance to corrosion and oxidation. While gold is an effective contact coating in many applications, alternatives to gold are desirable.